Answer:
D. Sterility Locus
Explanation:
Angiosperms have several mechanisms to prevent self-pollination due to the advantage of cross-pollination. One of such mechanisms is self-incompatibility genes present on the sterility locus.
These genes determine the germination of the pollen on the stigma. If both the pollen and stigma carry the same allele of the gene present at the sterility locus, the germination of pollen is prevented.
The sterility locus has multiple alleles and the presence of the same alleles at the same locus in both pollen and stigma prevents the pollen germination.
For example, pollen from S1S2 individuals can not germinate on the stigma with the S1S3 genotype. Here, the pollen does not obtain water as required for germination from the stigma and are unable to germinate.
Answer:
The rule of magnetism illustrated is the field lines are more concentrated at the poles and also about the direction of magnetic field.
Explanation:
- Every magnet has two pole, north pole and south pole. The like poles repel each other and unlike poles attract each other.
- The direction of magnetic field is from north to south that can be seen by the iron filling experiment.
- When the iron fillings are kept near the bar magnet, we observe that most of the fillings are attached to either poles.
- It is due to the fact that the concentration of magnetic field is highest at the poles.
You need to add the choices in order for someone to answer this question...
A plant reaches its adult stage
when it is ready to reproduce.
The statement “All plants
reproduce several times before dying” is true. The answer is letter A. Plants
can reproduce several times as long as it has the gametes needed for
reproduction.